# Andrew S. Tanenbaum (OS) Edition 4 Exercise 2 Question 42 (Page No. 177)

243 views
Explain how time quantum value and context switching time affect each other, in a round-robin scheduling algorithm.

There is an inverse relation between time quantum and context switching in a round robin scheduling as very high time quantum may lead to starvation , i.e. , other processes have to wait to more. If time quantum is small then there will be more context switching and more process will get time to be executed for lesser time period .

## Related questions

1 vote
1
191 views
Measurements of a certain system have shown that the average process runs for a time $T$ before blocking on $I/O$. A process switch requires a time $S$, which is effectively wasted (overhead). For round-robin scheduling with quantum $Q$, give a formula for the CPU efficiency for each of the following: $Q = \infty$ $Q > T$ $S < Q < T$ $Q = S$ $Q\: \text{nearly}\: 0$
Five batch jobs. $A$ through $E$, arrive at a computer center at almost the same time. They have estimated running times of $10, 6, 2, 4,$ and $8$ minutes. Their (externally determined) priorities are $3, 5, 2, 1,$ and $4,$ respectively, with $5$ being the highest ... the CPU. For $(b)$ through $(d),$ assume that only one job at a time runs, until it finishes. All jobs are completely CPU bound.
Five jobs are waiting to be run. Their expected run times are $9, 6, 3, 5,$ and $X$. In what order should they be run to minimize average response time? $($Your answer will depend on $X.)$